Every year, the APS Division of Fluid Dynamics hosts a physical Gallery of Fluid Motion at its annual meeting—a room where stunning graphics and videos from computational or experimental studies showing flow phenomena are displayed. The most outstanding entries are selected by a panel of referees for artistic content and honored for their originality and ability to convey information. Past winners are published in the journal Physics of Fluids.
The hidden complexities of the simple match
Victor A. Miller
Ronald K. Hanson
This video shows the complex but hidden flows created when lighting and extinguishing a strike-anywhere match. A high-speed camera running at 2,000 and 10,000 frames per second lets us slow down the events, visualizing the hidden dynamics of turbulence and combustion; schlieren imaging enables us to see changes in fluid density caused by the hot combustion products mixing with the cool ambient air.
Fluid jet guiding
Baptiste Darbois Texier
University of Liege
Japanese Kusari-doi play the role of the occidental gutter. Kusari-doi constitute a smart way to guide the rain from the roof to the ground avoiding splashing. The video shows variations about this theme. A rigid wire is shown to be an efficient manner to bow the rain. The fluid rivulet sticking to the wire becomes acrobatic: fighting against gravity, looping and spinning.
Oil Dispersion by Breaking Waves
Johns Hopkins University
This video shows experimental investigation on dispersion of a controlled oil slick by breaking waves with and without introduction of dispersant (Corexit 9500A) in a specialized wave tank. High-speed visualization reveals the evolution of an oil slick as it was either entrained into the water column along with air bubbles, or ejected into air together with water droplets. High-speed digital holography shows waves for DOR as low as 1:100 generate extensive micro-sized oil threads that then break up into micron-sized droplets.
Laser impact on a drop
Alexander L. Klein
Claas Willem Visser
Jacco H. Snoeijer
University of Twente
In this video we show that the response of a liquid drop to the impact of a nanosecond laser-pulse is violent: the drop gets strongly deformed and propelled forward at several m/s, and subsequently breaks up or even explodes. Detailed understanding of this process is of key importance for the generation of extreme ultraviolet (EUV) light in the latest nanolithography machines. Here we recorded the drop’s response to various laser-impact conditions by high-speed imaging at 20 000 frames per second (FPS) and by stroboscopic illumination at an effective frame rate of 10 million FPS.
Beer inspires anti-sloshing science
Princeton University & SVI (CNRS/Saint-Gobain)
Princeton University & ENS Cachan
New York University Polytechnic School of Engineering
Howard A. Stone
Sloshing, i.e. the oscillations of the free surface, is a practical and industrial challenge to liquid transportation. Walking with a beer teaches us that the presence of foam atop a liquid can damp the sloshing. Our study provides new insights into the science of sloshing by exploring the damping effect of foam in a cell as illustrated in the picture.
Karman vortex street
Lawrence Berkeley National Laboratory
This video shows an extended wake for flow past a cylinder in 2D depicting the Karman vortex street instability at unprecedented scale and resolution using an adaptive mesh refinement. Secondary, tertiary and even quaternary wake structures are captured. The Reynolds number is 300, which is in the transition to turbulence regime.
Vortex-wall interaction influencing heat transfer
RWTH Aachen University
The video shows the impingement of a submerged jet on a vertical plate by means of experiments (visualization by the injection of dye) and numerical simulations. The influence of vortices emerging in the shear zone on the local and instantaneous local heat transfer is visualized by a detailed examination of the numerical results.
Gels bouncing on hot surfaces
Brendan C. Blackwell
Athrey E. Nadhan
Randy H. Ewdolt
University of Illinois at Urbana-Champaign
This video shows high-speed imaging of gels impacting hot surfaces. At room temperature these materials tend to stick where they hit, but at sufficiently high temperature the dynamics change. This leads to the material exhibiting unique breakup dynamics and bouncing off of the impacting surfaces.
Raining on a beach
University of Minnesota
This set of videos show the impact of liquid drops on a granular surface — a ubiquitous phenomenon that is likely familiar to all of us who have watched raindrops splashing in a backyard or on a beach. The impact process creates impact craters of various fascinating shapes. Surprisingly, we found that these craters follow the same energy scaling and reproduce the same crater morphology as that of asteroid impact craters on planetary bodies.
Rain and Clouds
Max Planck Institute for Dynamics and Self-Organization
The video shows cloud patterns on top of a convecting fluid in a temperature gradient. The bottom fluid (ocean) is condensed Sulfurhexafluoride (SF6) and the top has an atmosphere of SF6 vapor with Helium. All is at a pressure of 56bar. Visible are clouds that from in the bottom turbulent boundary layer. In addition SF6 condenses on the top cold surface in a hexagonal pattern.